when vegeta's hair gets wet...does it fall down или is it the same???

I don't know how but it stays the same like how can his hair do that!

Actually, in the episode where Vegeta takes a душ at Bulma's house, it does go down...

I'm not sure, I don't remember the episodes well when his hair gets wet. I think it stays the same.

It stays the same.

it remains the same

beggining of android saga when vegeta wore that розовый рубашка he took a душ and was forced to wear it and in the душ it showed his hair going backwards like wind was blowing
(hope this helps)

it gose down

It goes down. For those who get this: The female species, what an enigma!